| Objective and quantitative evaluation of power system reliability can explore the weakness and point out a way for power system planning/optimization from the view of improving reliability, in order to achieve the goal of keep security, stability and reliability of power system operation. To avoid accidents and keep security, stability and economic, primary devices and its system of stable and reliable performance are not only needed, reliability of different levels of secondary systems are also put forward very high demand.The development of electronic technology, information technology and high-speed communication network technology promote the transformation of traditional substation to intelligent substation, and gradually entered a stage that is comprehensive constructing and in-depth application. The intelligent substation has a huge difference from the traditional substation in terms of structure of the system, communication form and practical application. Multiple cases of blackout in the worldwide also wake the people that the power system is a systemic project, including primary and secondary systems. Especially, under the rapid development background of the smart grid and intelligent substation, systematical and quantitative research and analysis on the substation secondary system and its impact on preliminary system is of considerable theoretical significance and engineering value.Firstly, this dissertation introduces the research about the reliability of the substation and the basic conceptions and main indexes of power system reliability. It elaborates common reliability analysis method. The system reliability analysis methodology for intelligent substation is also built. It introduced the system structure, key technology and development process of intelligent substation and has a depth research on hardware modules.Then, the reliability evaluation of secondary system has been analyzed based on the hardware modules of functional unit. Based on the effectiveness on the primary system, reliability model of secondary system is created by a system effectiveness approach including hardware module, interface module, functional module and effective module. And the FAT and series-parallel method is used to quantitatively evaluate the reliability of secondary systems of intelligent substation. Components importance analysis is demonstrated by variable parameters method in order to find the hardware modules that have a huge impact on the functional unit. It provides a guidance for optimization system, designing devices and the secondary system reliability. At last, the effect of the secondary systems failure probabilities on the primary system has been analyzed, so that a reliability model of intelligent substation is formed. We can model the whole operation sequences of functional events of the secondary systems and then, on the effectiveness of the proposed method of secondary system reliability assessment methods, further clarify how to specifically analyze the impact on the primary system reliability of secondary system. The possible results are clearly displayed by event tree. Finally, this approach creates the linkage between component reliability, system reliability of secondary systems and the reliability of the primary system, which can be further applied in the reliability evaluation of the intelligent substation and be proved the impact of the automation system application on the substation reliability by example. |
